The effect of using different levels of whey powder on milk yield and composition in Simmental cows

he present study was conducted to investigate the effect of using different levels of whey powder on milk yield and composition in Simmental cows. For this reason a total of eight Simmental cows (four nulliparous and four multiparous dairy cows) were randomly assigned to the 4 experimental treatments in Latin square design with 4 cows each. The experimental period lasted 56 days. The cows were feed by basal diet as control, 3, 6 and 12 percentages of whey powders in their daily diets respectively. The result indicated that the feed intake (kg/d) was increased by using different levels of whey powder. Data showed that there were no significant effects between treatments about feed intake compared to the control. The result showed that the milk protein percentage was increased none significantly by whey powder compared to the control. Milk fat induced and percentage milk protein improved as a result of whey powder supplementation. Data from current study indicate that the milk lactose, milk non-fat solids and milk total solids values in the treatments are none significantly different. As result revealed milk somatic cell increased when cows were fed by different levels of whey powder and their number increased with increasing consumption of whey powder. The presented results in this study showed that Milk urea nitrogen had decreased by whey powder, but Milk urea had tended to increase significantly (P≤0.05). It seems that using different levels of whey powder could positive effects on feed intake, milk yield and its composition on Holstein dairy cows.